Full of forethought; showing careful thinking about future possibilities; thoughtfully planned.
From forethought + -ful (suffix meaning 'full of'). This creates an adjective emphasizing that someone is particularly characterized by good advance planning.
Notice how 'forethoughtful' sounds almost identical to 'thoughtful'—that's because the 'fore' prefix adds the dimension of thinking ahead, which is what makes planning truly thoughtful!
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